With gcov, is it possible to merge to .gcda files?

Question

I have the same source files (C and Obj-C) being compiled into two targets: the unit test executable and the actual product (which then gets integration tested). The two tar

Answer 1

I merge it by lcov multi -d parameters as below. It works.

lcov -c -d ./tmp/ -d ./tmp1/ -o ./tmp/coverage.info

Answer 2

Since you're using lcov, you should be able to convert the gcov .gcda files into lcov files and merge them with lcov --add-tracefile.

From manpage: Add contents of tracefile. Specify several tracefiles using the -a switch to combine the coverage data contained in these files by adding up execution counts for matching test and filename combinations.

Answer 3

Finally I managed to solve my problem by means of lcov.

Basically what I did is the following:

• Compile the application with the flags -fprofile-arcs -ftest-coverage --coverage
• Distribute the copy of the application to each node.
• Execute the application in each node in parallel. (This step generates into the application directory in the access host the coverage information)
• Let lcov make his work:
  • lcov --directory src/ --capture --output-file coverage_reports/app.info
• Generate the html output:
  • genhtml -o coverage_reports/ coverage_reports/app.info

I hope this can be of help to someone.

Answer 4

I think the intended way to do this is not to combine the .gcda files directly but to create independent coverage data files using

lcov -o unittests.coverage -c -d unittests
lcov -o integrationtests.coverage -c -d integrationtests

Each coverage data then represents one "run". You can of course create separate graphs or html views. But you can also combine the data using --add-tracefile, -a for short

lcov -o total.coverage -a unittests.coverage -a integrationtests.coverage

From the total.coverage you can generate the total report, using genhtml for example.